This invention relates to telecommunications equipment such as optical fiber distribution frames.
Optical fiber distribution frames, such as AT&T's lightguide cross-connect (LGX.RTM.) distribution frame, serve the function of coupling incoming fiber optic cables to customer equipment. The frame typically includes a multiplicity of shelves, each shelf including a single or plurality of modules where the optical connections are made to the fibers of the incoming cable. Cross-connect jumper cables (also known as patch cords) are applied in the front of the apparatus between the panels which are to be optically connected (see, e.g., U.S. Pat. No. 4,630,886 issued to Lauriello et at.).
One of the problems which exists in typical frames is the high density of optical connections, typically 72-144 connections per shelf. The great number of cross-connections makes it very difficult to be able to determine if both ends of a jumper cable are properly connected.
In order to trace the fiber connections, it has been proposed to provide at one end of each jumper cable a light source which launches a light signal through the fiber jacket to light both ends of the jumper (see, e.g., U.S. Pat. No. 5,305,405 issued to Emmons et al.).
It is desirable to have an optical fiber distribution frame which gives an indication of where the fiber jumper cables should be connected, either for purposes of making the connection, or once the connection is made, to be able to tell where the opposite ends of a particular cable are connected. It is desirable to do this without an active light source involved in the tracing.